Methods and systems for verifying and monitoring endotracheal tube position during intubation

ABSTRACT

An endotracheal tube positioning device includes a first Hall sensor, a second Hall sensor spaced a predetermined distance from the first Hall sensor, a converter, and an integrated circuit board electrically connecting the first Hall sensor and the second Hall sensor to the converter, wherein a position range is established for the device based on a symmetry of voltage readings provided from the first and second Hall sensors to the converter. An endotracheal tube positioning system includes an endotracheal tube having a magnet provided toward a distal tip end, an endotracheal tube positioning device having a first Hall sensor and a second Hall sensor, the positioning device configured to adhere to a skin surface, and a monitor for receiving data based on voltage values provided by the first and second Hall sensors, the data indicating a position of the magnet relative to the adhered position of the positioning device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 61/784,043, entitled, “METHODS AND SYSTEMS FOR VERIFYING ANDMONITORING ENDOTRACHEAL TUBE POSITION DURING INTUBATION,” filed Mar. 14,2013, which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The invention generally relates to endotracheal tube (ETT) placement,and, more particularly, to methods and systems for verifying andmonitoring ETT position during intubation.

BACKGROUND OF THE INVENTION

Criticality of ETT placement during intubation has traditionallyrequired the use of capnographic monitoring as well as radiographimaging to avoid esophageal or bronchial installation. Either of thesemisplacement scenarios can result in inadequate patient ventilation andpossible asphyxiation. In addition to the initial verification of theETT device placement, subsequent verification radiographs are typicallyperformed on a daily basis for patients requiring extended periods(e.g., days) of intubation.

A need exists for methods and systems that eliminate the expense andradiation exposure of repeated radiographs for intubated patients byproviding a mechanism to verify ETT position through continuousmonitoring and/or via an external reference or fiducial applied to theskin surface.

SUMMARY OF THE INVENTION

The foregoing needs are met by the present disclosure, wherein accordingto certain aspects, an endotracheal tube positioning device includes afirst Hall sensor, a second Hall sensor spaced a predetermined distancefrom the first Hall sensor, a converter, and an integrated circuit boardelectrically connecting the first Hall sensor and the second Hall sensorto the converter, wherein a position range is established for the devicebased on a symmetry of voltage readings provided from the first andsecond Hall sensors to the converter.

In accordance with yet other aspects of the present disclosure, anendotracheal tube positioning system includes an endotracheal tubehaving a magnet provided toward a distal tip end, an endotracheal tubepositioning device having a first Hall sensor and a second Hall sensor,the positioning device configured to adhere to a skin surface, and amonitor for receiving data based on voltage values provided by the firstand second Hall sensors, the data indicating a position of the magnetrelative to the adhered position of the positioning device.

In accordance with yet other aspects of the present disclosure, a methodof positioning an endotracheal tube in a patient for intubation includesdirecting a distal tip end of the endotracheal tube through a glottis,the distal tip end having a magnet embedded therein, positioning thedistal tip end at an home position in a mid-trachea region of thepatient, affixing a sensing device just above or at a sternal notch ofthe patient, wherein the sensing device includes a first Hall sensor anda second Hall sensor positioned a predetermined distance from the firstHall sensor, reading with the sensing device an intensity of themagnetic field produced by the magnet using the first Hall sensor andthe second Hall sensor, transmitting signals from the first Hall sensorand the second Hall sensor to a display device based on a voltage outputsensitive to the intensity of the sensed magnetic field, determining alongitudinal displacement There has thus been outlined, rather broadly,certain aspects of the present invention in order that the detaileddescription herein may be better understood, and in order that thepresent contribution to the art may be better appreciated.

In this respect, before explaining at least one embodiment of theinvention in detail, it is to be understood that the invention is notlimited in its application to the details of the construction and to thearrangements of the components set forth in the following description orillustrated in the drawings. The invention is capable of embodiments inaddition to those described and of being practiced and carried out invarious ways. Also, it is to be understood that the phraseology andterminology employed herein, as well as the abstract, are for thepurpose of description and should not be regarded as limiting.

As such, those skilled in the art will appreciate that the conceptionupon which this disclosure is based may readily be utilized as a basisfor the designing of other structures, methods and systems for carryingout the several purposes of the present invention. It is important,therefore, that the claims be regarded as including such equivalentconstructions insofar as they do not depart from the spirit and scope ofthe present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an endotracheal tube, in accordance with aspects ofthe present disclosure;

FIG. 2 illustrates a monitoring device, in accordance with aspects ofthe present disclosure;

FIG. 3 shows an exploded view of a monitoring device, in accordance withaspects of the present disclosure;

FIG. 4 is a block diagram illustrating components of a monitoringdevice, in accordance with aspects of the present disclosure;

FIG. 5 illustrates a positioning device, in accordance with aspects ofthe present disclosure;

FIG. 6 illustrates an endotracheal tube and a positioning device in astate of use, in accordance with aspects of the present disclosure;

FIG. 7 is a close up frontal view of an endotracheal tube and apositioning device in a state of use, in accordance with aspects of thepresent disclosure;

FIG. 8 illustrates a top view of an endotracheal tube and a positioningdevice in a state of use, in accordance with aspects of the presentdisclosure;

FIG. 9 illustrates an ETT tube monitoring system, in accordance withaspects of the present disclosure;

FIG. 10 illustrates an example of a predetermined radius polynomialseries, in accordance with aspects of the present disclosure;

FIG. 11 shows an exemplary display illustrating aspects of monitoringplacement of an ETT using a positioning device, in accordance withaspects of the present disclosure;

FIG. 12 shows another view of an exemplary display illustrating aspectsof monitoring placement of an ETT using a positioning device, inaccordance with aspects of the present disclosure;

FIGS. 13 and 14 illustrate a method for monitoring placement of an ETTusing a positioning device, in accordance with aspects of the presentdisclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

The methods and systems disclosed herein enable precise tracking andcontrol of the position of an ETT during intubation of a patient. Asshown in FIG. 1, an ETT 10, which may be made from polyvinyl chloride(PVC) or any other suitable material, has a proximal end 20 and a distaltip end 30. The ETT may be used to establish a patient airway during amedical procedure by inserting the distal tip end 30 of the ETT into thetrachea, typically through the mouth, which procedure is known asintubation. Once inserted to a correct position in the trachea, a cuffballoon 40 may be inflated in an attempt to lock the ETT at the correctposition. Once established, the ETT may be used to deliver gases, suchas oxygen, helium, nitrous oxide, to name a few, drugs, including thoseused for general anesthesia and medicines, and/or to provide a pathwayfor mechanical ventilation to a patient when the proximal end 20 of theETT is coupled to a mechanical ventilator, for example.

Placement of the ETT is critical during intubation to avoid esophagealor bronchial installation. Either of these misplacement scenarios canresult in inadequate patient ventilation and possible asphyxiation.Today's standard of care involves intubating the patient with the ETT sothat the distal tip end 30 is directed through the glottis andpositioned in the mid-trachea approximately 2 cm above the bifurcationof the carina. Capnography may be used to verify initial placement. Inaddition, the patient is often given a chest x-ray to confirm the properplacement of the ETT by visualizing the placement of the distal end tip30 with respect to the carina.

Due to many factors, including each patient's individual physiology, apatient's voluntary or involuntary attempts to extubate the ETT, and thefact that patients are subjected to movement during a procedure and/ortransport, there is ample opportunity for the distal end tip 30 of theETT to move from the initially confirmed position. Accordingly,particularly during extended intubation of a patient over multiple days,each intubated patient is often subjected to at least one and oftenmultiple confirmatory x-rays every day the patient is intubated toensure proper positioning of the ETT.

Aspects of the present disclosure provide methods and systems formonitoring the proper placement of the ETT by transcutaneousdetermination of the position of the distal end tip 30 of the ETT. Asshown in FIG. 1, a miniature rare earth magnet 50 may be embedded in alumen wall of the ETT 10 near the distal end tip 30. The magnet 50 maybe radially polarized to provide the greatest B-field flux density in aplane orthogonal to a circumferential surface (not edge) of the magnet50.

As illustrated in FIGS. 2 and 3, a small battery powered hand helddevice 100 may be used to transcutaneously measure the intensity of theB-field. The device 100 may include a housing 110 having an upperhousing portion 112 and a lower housing portion 114 coupled together toform a handle portion 120 at a proximal end, a central body portion 130,and a sensing tip portion 140 extending from a distal end of the bodyportion 130. The upper housing portion 112 and lower housing portion 114may be coupled, for example, by press or snap fit and/or by any suitableattachment means, including screws, tabs, and adhesives, to form ahollow interior chamber 150 for mounting and protecting a power source160, such as a battery, and electrical circuitry, some of which may beimplemented via an Integrated Circuit Board (ICB) 170. The sensing tipportion 140 of the housing may be an integrally formed feature of thehousing 110 and/or all or a portion of the sensing tip portion 130 maybe separately formed, as shown in FIG. 3, and attached to the housing110.

As shown in FIG. 3, a ratiometric Hall sensor 180 may be mounted andretained in a tip end 142 of the sensing tip portion 140 of the device100. FIG. 4 illustrates aspects of the electrical circuitry of thedevice 100, which may include various means for electrically connectingto the sensor 180 an analog amplifier and signal conditioning circuit200, a micro controller and signal processor 210, a user interface 220,a micro controller power regulation circuit 230, a battery chargercircuit 240, and/or the power source 160, which may be a battery, forexample. An output of the sensor 180 measures the Hall voltage, whichmay be conditioned, amplified, and passed to a 12 bit analog to digitalconversion stage via the analog amplifier and signal conditioningcircuit 200. The digital Hall voltage value may then be interpreted byan algorithm executing within the micro controller and signal processor210. The device 100 may permit the user to null the B-field signal inorder to eliminate the influence of any spurious environmental B-fields.

As the device sensor 180 approaches a B-field source, the device 100 mayprovide both visual and audio indication of absolute field intensity viathe user interface 220. For example, a visual indicator 222 may consistof a 16 element bar graph of Light Emitting Diodes (LEDs), as shown inFIG. 3, and an audio indication may provide the user with a constantpitch, frequency varying tick via an audio device 224. The visualindicator 222 may employ a peak hold mechanism, wherein if a B-fieldsource is approached and then passed, the peak value LED will remainilluminated although the graph elements inferior to the peak LED willcontinue to respond dynamically to the B-field value. The illuminationof peak value LED will be maintained until the user initiates a nullprocess, which may be by pressing a control button 250 (see FIG. 2). Thecontrol button 250 may also provide on/off control of the device, whichmay be by pressing the button 250 for an extended time compared to, forexample, activation of the null process which may be accomplished by aone-time pressing of the button 250.

Following radiograph or x-ray verification of correct ETT positioning,the Hall sensing device 100 may be swept over the patient's throat,preferably by approaching the patient's sternal notch from above orbelow. The visual and audio indicators, 222 and 224, will provide a peakvalue hold condition when the sensor tip sensor 180 is located directlyabove the magnet 50, indicating the ETT tip position. A fiducial, suchas an adhesive patch or ink, may then be applied on the patient's skincorresponding to the location of the tip end 142 of the device 100. TheHall effect ETT position can now be re-verified at any time bypositioning the tip end 142 of the Hall sensor device 100 over thefiducial or re-sweeping the Hall sensor device 100 to establish theextent of ETT displacement from the original verified position. Ifdisplaced, a clinician could reposition the ETT by further intubatingand/or extubating, i.e., pushing in or pulling back, the ETT accordingto the noted distance of displacement. The process may be repeated untilthe clinician has verified the ETT is once again at the proper placementposition as initially determined for maximum safety and effectiveness.

Configuration testing indicates reproducible position detection accuracyof +/−5 mm through 40 mm of tissue analog. These accuracy estimates arewell within the nominal distance from larynx to carina for normalpositioning of the ETT for effective ventilation.

In accordance with yet other aspects of the present invention, FIG. 5illustrates a dual sensor device 300 useful for continuous monitoring ofthe ETT position in a patient. The dual sensor device 300 may be formedto house a first Hall sensor 305 and a second Hall sensor 310. Twosensors allow a refined determination of the distance of migration ofthe ETT 10 from an ideal initially determined position as well as thedirection of migration of the ETT 10 from the ideal initially determinedposition. Because the dual sensor device 300 may be affixed to thepatient for continuous monitoring, the sensor device 300 allows forautonomous repositioning of the ETT without having to hold or sweep thesensor device 300 to obtain a Hall voltage reading for positiondetermination.

As shown in FIG. 5, the two Hall voltage sensors 305 and 310 may bemounted in the sensor device 300 at a set distance apart, preferablyabout 1 cm apart along a longitudinal centerline A of the device 300. Asmall ICB 315 (see FIG. 8) may be used to mount the sensors 305 and 310and associated electrical circuits.

As shown in FIGS. 6 and 7, the device 300 may be affixed to a patient400 just above or at the sternal notch 402. The ETT 10 may be insertedso that the distal tip end 30 is directed through the glottis andpositioned in the mid-trachea 404 approximately 2 cm above thebifurcation of the carina 406. The cuff 40 may be inflated to establishand secure the ETT in position. Capnography may be used to verifyinitial placement. In addition, the patient may be given a chest x-rayto confirm the proper placement of the ETT 10 by visualizing theplacement of the distal end tip 30 with respect to the carina 406.

As shown in FIG. 8, the device 300 may be composed of a skin barrierlayer, for example, over-molded with silicone, so that the device may beeasily affixed in position against the skin surface 412. The ICB 315 andsensors 305/310 may be mounted into a housing structure or the siliconemay be over-molded over the ICB 315 and sensors to form a body 320. Thedevice 300 may be shaped similar to a bandaid, for example, forefficient visual directional coordination when affixing the sensordevice 300 to a patient.

As shown in FIG. 9, signals from the sensors 305 and 310 in thepositioning device 300 may be electrically conducted via fourconductors, typically a 5V conductor and a ground connection for each ofthe sensors, via a tether 330 connected to a monitoring apparatus 340.With the ETT 10 inserted through the larynx 414 and positioned in thetrachea 404, the Hall sensors 305 and 310 in the positioning device 300produce a voltage output sensitive to the intensity of the magneticfield produced by the magnet 50. The sensors 305 and 310 may have asensitivity of 5 mv/gauss, for example.

Referring back to FIG. 8, by using a cylindrical coordinate system,wherein the ETT 10 is defined as being a substantially cylindrical unit,any point on the ETT 10 may be defined according to a longitudinalcoordinate along the length of the ETT 10 and a corresponding radialcoordinate along the circumference of the ETT 10. Accordingly, once aninitial position of the ETT is determined, the sensor device 300 may beused to determine longitudinal displacement of the ETT 10 as well as anangle of rotation θ of the ETT 10 from a polar axis 350 established whenthe magnet 50 is anteriorly aligned with the sensors 305/310.

The magnetic field 55 of the magnet 50 may be defined according to thechoice of magnet material over a region and cylindrical radius toaccommodate substantially any patient anatomy. A series of curves may bederived to represent the magnetic field as the sensor moves in thelongitudinal axis and as a function of radial rotation. Rather than uselarge look up tables corresponding to predetermined experimental valuesof magnetic field strength for every possible longitudinal and radialpoint with respect to the sensor positions, higher order polynomialequations may be derived to fit to the predetermined curves so themagnetic field strength with respect to each sensor may be determined atany given longitudinal and radial point with respect to a central axisof an ETT of given radius. Thus, for every point in the cylindricalcoordinate system, two unique sensor values may be determined. Bymapping the baseline coordinate system to the initial confirmed positionfor an ETT of radius Z, the predetermined polynomials may be used todetermine subsequent changes in position based on new sensor values,which may be continuously monitored.

For example, as shown in FIG. 10, for an ETT 10 having a radius Z of 20mm, a predetermined radius polynomial series may be used to determinethe longitudinal position relative to an ETT home reference, also takinginto account an angle correction coefficient. The recorded Hall voltageH1V of the first sensor 305 and the Hall voltage H2V of the secondsensor 310 may be used in the radius polynomial, for example, todetermine the longitudinal position of the ETT 10 in the trachea basedon calculated relative longitudinal positions H1P and H2P.

As shown in FIGS. 7 and 8, with the ETT 10 in the initial confirmedproper position, the sensor 300 may be located near the sternal notch ona patient. Because the magnet 50 is in a known radial position in thetrachea, preferably nearest the anterior portion of the throat,longitudinal movement of the sensor 300 up or down along the centerlineA (see FIG. A), substantially parallel to a central axis of the trachea,will allow the clinician to set the center point position of the sensor300, which may be referred to as the “Home” position. As shown in FIGS.11 and 12, the two Hall voltage signals may be processed and displayedon the monitoring apparatus 340, such as a portable electronic device ora computer monitor, for example, in a way that is easy for the clinicianto decipher. FIG. 11 illustrates the Home position in which a centerreference line 342 on the display indicates that the magnet islongitudinally centered between the two Hall sensors 305, 310. In FIG.12, the monitoring apparatus 340 shows, for example, that the centerline342 has shifted, indicating that the ETT 10 has moved and/or rotatedsuch that the magnet 50 is closer to one of two sensors 305, 310 andfurther from the other one of the two sensors 305, 310. In accordancewith certain aspects of the present disclosure, an audio and/or visualalarm may be activated if the device 300 detects movement of the magnet50 beyond a certain predetermined range. In accordance with yet otheraspects of the present disclosure, as shown in FIG. 9, the signalsreceived and processed by the monitoring apparatus 340 may be sent, forexample, via an interface 360, such as a radio frequency interface, to aremote receiver 362. Thus, a technician may monitor or be alerted byalarm, for example, to the position of the ETT in any given patient, oreven a plurality of patients, without having to be physically present.The continuous and/or remote monitoring capabilities of the positioningdevice 300 provide a safe, effective method of tracking ETT positionwithout the need to manually observe or periodically assess the positionwith x-ray, for example.

FIGS. 13 and 14 illustrating a method of monitoring ETT positioningusing the positioning device 300 and an ETT with an embedded magnet 50.Beginning with FIG. 13, the positioning device 300 must first becalibrated. With the ETT verified to be in a desired position, thepositioning device 300 may first be placed near the sternal notch of thepatient. A sweeping of the device 300 up and down longitudinally allowsthe Hall sensors 305 and 310 to begin reading the intensity of themagnetic field of the magnet 50 embedded at a particular longitudinalposition of the ETT. As shown at 602 and 604, each of the Hall sensorsin the device 300 generate a respective voltage according to theintensity of the magnetic field that is output to an analog/digitalconverter 606. The converter 606 reads the output from the sensors,including a maximum upper limit range indicator reading (see FIG. 11)corresponding to, for example, a maximum longitudinal distance in onedirection where a signal from one of the sensors 305 or 310 becomesnegligible. A maximum lower limit range indicator reading may similarlybe produced corresponding to an opposite maximum range produced when areading from the other of the sensors 305 or 310 becomes negligible.Anywhere beyond the maximum upper limit or maximum lower limit and thevoltage readings of one and/or both of the sensors indicate the device300 is not in proper position for adequate fine tuning positionaladjustment in order to affix the device 300 at a “home” position forcontinuous monitoring. Thus, as shown in FIG. 13, if either of the upperor lower range limits are reached as read by the converter at step 608,a range error may be generated at 610 or 612 depending on which sensor305 or 310 is essentially beyond range for obtaining an adequate voltagereading. Additional readings are read by the converter 606 until thereading indicates that both sensors 305 and 310 are providing readingsto the converter 606 within the acceptable limits.

An adequate range reading is established based on symmetry of thesensors 305 and 310 in relation to the magnet 50. When centered in thehome position, as shown in FIG. 11, each sensor reads an approximatelyequal value with respect to the intensity of the magnetic field and acenterline may be used to indicate on a display to the user that thedevice 300 is properly centered and in position. As the device 300 ismoved up or down, one sensor will read an increasing intensity and theother sensor will read a decreasing intensity of the magnetic field.Referring back to FIG. 13, once the device 300 passes the upper andlower limit test at 608, the scaled display may be updated at step 614.The centerline 342 shown in FIGS. 11 and 12 may be updated to reflectmovement of the range based on each of the voltage readings 602 and 604received by the converter 606. At step 616, the readings andconfiguration of the display are continuously updated until the voltagereadings of each sensor are approximately equal, at which point the usermay indicate that the device 300 is in the proper home position at step618. Once the home position is established, at step 620 the radiuspolynomial for an ETT of given radial dimension is applied to the Hallvoltage readings established for the home position, setting a homelongitudinal reference value for each of the sensors, H1P and H2P, and ahome angle reference value which is the sensor axis rotational positionrelative to the ETT home reference. The longitudinal range may beestablished by adding the H1P value to the H2P value.

At step 622, for each successive sensor reading, an offset is determinedto see if the ETT has moved relative to the static home position of thepositioning device 300. If the values of H1P and H2P are equal, whereinthe sensors are symmetrically aligned around the magnet, as is the casewhen the device 300 is in the home position, then an offset, which isH1P-H2P, is zero, indicative that the ETT has not moved. As shown atstep 624, the H1P and H2P values remain the same, as does the rangevalue, for example. However, if successive readings taken at step 620establish at step 622 that there is an offset, the new values of H1P andH2P are determined at step 626 and recorded at step 628. As shown inFIG. 14, it is determined at step 630 whether the offset recorded atstep 628 is the same as the previous offset reading or if the ETT hasexperienced additional displacement. If the offset value is the same asthe previous reading, a range reading is taken at step 632. If the rangereading is the same as the previous range reading, the angle has notchanged and the angle is set at step 634 to be the same as that of theprevious offset. If, however, the range is different at step 632, therange difference is noted at step 636. At step 638, an angle function isapplied based on the range difference to determine at step 640 a newangle of rotation. In this case, the range difference occurs when thelongitudinal offset has not changed but the voltage readings of thesensors 305 and 310 indicate a rotational change in the position of themagnet 50. The new angle is submitted to update the user interface atstep 642.

Referring back to step 630, if it is determined that the offset of thecurrent reading is different from the offset of the previous reading, arange normalization is performed at step 650 and the normalized range iscompared to the previous range reading at step 652. If the rangereadings are equal, indicating that the angle of rotation has notchanged, the angle determination at step 634 is the same as that of theprevious angle. In this case, the new offset is indicative of alongitudinal movement of the device 300, which is provided to the userinterface display at step 642. If, however, at step 652, the rangereading differs from the previous range reading, the previous angle isnoted at step 654 and a range difference determined at step 656 is usedto determine a new angle at step 658. The new angle may be provided tothe user interface display at 642.

In step 660, the offset value is compared to a threshold offset value todetermine if an alarm or alert must be sent to notify a technician thatthe ETT has moved. The user interface display data at 642 may be updatedas shown at 662 and 664 depending on whether an alarm situation isindicated. The technician may reposition the ETT based on the systemfeedback until the offset is nullified.

In accordance with yet other aspects of the present invention, as shownin FIG. 9, for example, a cuff pressure monitor 370 may be used toprovide cuff pressure data to the user interface display 642. In thismanner, as shown in FIG. 14, step 670 may include determining whetherthe cuff pressure is above or below a threshold value such that an alarmor alert must be sent to notify a technician. The user interface displaydata at 642 may be updated as shown at 672 and 674 depending on whetheran alarm situation is indicated. At step 680, a sensor output istriggered and the entire process is repeated beginning with the voltagereadings at 602 and 604 being provided to the converter 606.

It is to be understood that any feature described in relation to any oneaspect may be used alone, or in combination with other featuresdescribed, and may also be used in combination with one or more featuresof any other of the disclosed aspects, or any combination of any otherof the disclosed aspects.

The many features and advantages of the invention are apparent from thedetailed specification, and, thus, it is intended by the appended claimsto cover all such features and advantages of the invention which fallwithin the true spirit and scope of the invention. Further, sincenumerous modifications and variations will readily occur to thoseskilled in the art, it is not desired to limit the invention to theexact construction and operation illustrated and described, and,accordingly, all suitable modifications and equivalents may be resortedto that fall within the scope of the invention.

What is claimed is:
 1. A method of positioning an endotracheal tube in apatient for intubation, the method comprising: providing a sensingdevice; directing a distal tip end of the endotracheal tube through aglottis, the distal tip end having a magnet embedded in a lumen wall ofthe endotracheal tube; positioning the distal tip end at a home positionin a mid-trachea region of the patient; affixing the sensing device justabove or at a sternal notch of the patient, wherein the sensing deviceincludes a first Hall sensor and a second Hall sensor positioned at apredetermined distance from the first Hall sensor; reading with thesensing device an intensity of a magnetic field produced by the magnetusing the first Hall sensor and the second Hall sensor; receiving, witha display device in communication with one or more processors, signalsfrom the first Hall sensor and the second Hall sensor in the sensingdevice corresponding to a voltage output that is sensitive to anintensity of the magnetic field; defining, with the one or moreprocessors, any point on the endotracheal tube according to alongitudinal coordinate along a length of the endotracheal tube and acorresponding radial coordinate along a circumference of theendotracheal tube using a cylindrical coordinate system; establishing ahome position of the sensing device and applying a radius polynomial forthe endotracheal tube to the Hall sensor readings established for thehome position of the sensing device, setting a home longitudinalreference value for each of the Hall sensors and a home angle referencevalue indicative of a relative rotation of the endotracheal tube withrespect to each of the Hall sensors; determining, with the one or moreprocessors, a longitudinal displacement of the endotracheal tuberelative to the home position of the sensing device based on signals ofsuccessive sensor readings of the first and second Hall sensors;determining, with the one or more processors, a radial displacement ofthe endotracheal tube relative to the home position based on the signalsof the successive sensor readings of the first and second Hall sensorswhen the magnet is anteriorly aligned with both the first and secondHall sensors, and displaying, with the display device, a displaycorresponding to at least one of the longitudinal displacement and theradial displacement.
 2. The method of positioning an endotracheal tubeof claim 1, wherein the home position is approximately 2 centimetersabove a bifurcation of a carina of the patient.
 3. The method ofpositioning an endotracheal tube of claim 1, further comprising:verifying the home position of the distal tip end with respect to thecarina via a visualization means.
 4. The method of positioning anendotracheal tube of claim 1, further comprising: sending an audioand/or visual alarm when the sensing device detects the longitudinal orradial displacement of the endotracheal tube beyond a predeterminedrange.
 5. The method of positioning an endotracheal tube of claim 1,wherein the sensing device is affixed at a position corresponding to thehome position of the endotracheal tube based on Hall voltage readingsproduced by the first Hall sensor and the second Hall sensor indicatingeach Hall sensor is reading an equal intensity of the magnetic field. 6.The method of positioning an endotracheal tube of claim 1, furthercomprising: connecting the display device to the sensing device forreceiving data based on voltage values provided by the first Hall sensorand the second Hall sensor, wherein the display device is a monitor andthe data indicates a position of the magnet relative to the affixedposition of the sensing device.
 7. The method of positioning anendotracheal tube of claim 1, wherein the magnet is longitudinallycentered between the first and second Hall sensors when the distal tipend of the endotracheal tube is at the home position.
 8. The method ofpositioning an endotracheal tube of claim 1, wherein establishing thehome position of the sensing device is based on the signals from thefirst and second Hall sensors, the home position of the sensing deviceindicating each respective signal from the first and second Hall Sensorsis approximately equal.
 9. A method of positioning an endotracheal tubehaving a radial dimension in a patient for intubation, the methodcomprising: positioning a distal tip end of the endotracheal tube in amid-trachea region of the patient, the distal tip end of theendotracheal tube having a magnet embedded therein; providing a sensordevice including a first Hall sensor and a second Hall sensor, the firstand second Hall sensors spaced apart by a predetermined distance;placing the sensor device just above or at a sternal notch of thepatient; sensing, with the first Hall sensor and the second Hall sensor,a magnetic field produced by the magnet embedded in the endotrachealtube when the magnet is anteriorly aligned with both the first andsecond Hall sensors; determining a home position of the sensor devicebased on Hall voltage readings produced by the first and second Hallsensors indicating each Hall sensor is reading an approximately equalintensity of the magnetic field, and setting a home longitudinalreference value for each Hall sensor and a home angle reference valueindicative of a relative rotation of the endotracheal tube with respectto each of the Hall sensors; receiving data for successive sensorreadings based on voltage values provided by the first and second Hallsensors, the data indicating a position of the magnet of theendotracheal tube relative to the position of the sensor device;determining, from the data, a longitudinal offset value based on alongitudinal displacement determined when one of the first or secondHall sensors reads an increasing intensity of the magnetic field and theother one of the first or second Hall sensors reads a decreasingintensity of the magnetic field; determining, from the data, arotational change in the position of the magnet; and displaying on amonitoring apparatus at least one of the longitudinal displacement ofthe endotracheal tube relative to the sensor device and the rotationalchange of the endotracheal tube relative to the sensor device.
 10. Themethod of positioning an endotracheal tube of claim 9, furthercomprising activating an audio and/or visual alarm if the sensor devicedetects movement of the endotracheal tube beyond a predetermined range.11. The method of positioning an endotracheal tube of claim 10, whereinthe predetermined range includes a longitudinal component and a radialcomponent.